DBConfiguration.java
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- /**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements. See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership. The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.apache.hadoop.mapred.lib.db;
- import java.sql.Connection;
- import java.sql.DriverManager;
- import java.sql.SQLException;
- import org.apache.hadoop.mapred.JobConf;
- import org.apache.hadoop.mapred.lib.db.DBInputFormat.NullDBWritable;
- /**
- * A container for configuration property names for jobs with DB input/output.
- * <br>
- * The job can be configured using the static methods in this class,
- * {@link DBInputFormat}, and {@link DBOutputFormat}.
- * <p>
- * Alternatively, the properties can be set in the configuration with proper
- * values.
- *
- * @see DBConfiguration#configureDB(JobConf, String, String, String, String)
- * @see DBInputFormat#setInput(JobConf, Class, String, String)
- * @see DBInputFormat#setInput(JobConf, Class, String, String, String, String...)
- * @see DBOutputFormat#setOutput(JobConf, String, String...)
- */
- public class DBConfiguration {
- /** The JDBC Driver class name */
- public static final String DRIVER_CLASS_PROPERTY = "mapred.jdbc.driver.class";
-
- /** JDBC Database access URL */
- public static final String URL_PROPERTY = "mapred.jdbc.url";
- /** User name to access the database */
- public static final String USERNAME_PROPERTY = "mapred.jdbc.username";
-
- /** Password to access the database */
- public static final String PASSWORD_PROPERTY = "mapred.jdbc.password";
- /** Input table name */
- public static final String INPUT_TABLE_NAME_PROPERTY = "mapred.jdbc.input.table.name";
- /** Field names in the Input table */
- public static final String INPUT_FIELD_NAMES_PROPERTY = "mapred.jdbc.input.field.names";
- /** WHERE clause in the input SELECT statement */
- public static final String INPUT_CONDITIONS_PROPERTY = "mapred.jdbc.input.conditions";
-
- /** ORDER BY clause in the input SELECT statement */
- public static final String INPUT_ORDER_BY_PROPERTY = "mapred.jdbc.input.orderby";
-
- /** Whole input query, exluding LIMIT...OFFSET */
- public static final String INPUT_QUERY = "mapred.jdbc.input.query";
-
- /** Input query to get the count of records */
- public static final String INPUT_COUNT_QUERY = "mapred.jdbc.input.count.query";
-
- /** Class name implementing DBWritable which will hold input tuples */
- public static final String INPUT_CLASS_PROPERTY = "mapred.jdbc.input.class";
- /** Output table name */
- public static final String OUTPUT_TABLE_NAME_PROPERTY = "mapred.jdbc.output.table.name";
- /** Field names in the Output table */
- public static final String OUTPUT_FIELD_NAMES_PROPERTY = "mapred.jdbc.output.field.names";
- /**
- * Sets the DB access related fields in the JobConf.
- * @param job the job
- * @param driverClass JDBC Driver class name
- * @param dbUrl JDBC DB access URL.
- * @param userName DB access username
- * @param passwd DB access passwd
- */
- public static void configureDB(JobConf job, String driverClass, String dbUrl
- , String userName, String passwd) {
- job.set(DRIVER_CLASS_PROPERTY, driverClass);
- job.set(URL_PROPERTY, dbUrl);
- if(userName != null)
- job.set(USERNAME_PROPERTY, userName);
- if(passwd != null)
- job.set(PASSWORD_PROPERTY, passwd);
- }
- /**
- * Sets the DB access related fields in the JobConf.
- * @param job the job
- * @param driverClass JDBC Driver class name
- * @param dbUrl JDBC DB access URL.
- */
- public static void configureDB(JobConf job, String driverClass, String dbUrl) {
- configureDB(job, driverClass, dbUrl, null, null);
- }
- private JobConf job;
- DBConfiguration(JobConf job) {
- this.job = job;
- }
- /** Returns a connection object o the DB
- * @throws ClassNotFoundException
- * @throws SQLException */
- Connection getConnection() throws ClassNotFoundException, SQLException{
- Class.forName(job.get(DBConfiguration.DRIVER_CLASS_PROPERTY));
- if(job.get(DBConfiguration.USERNAME_PROPERTY) == null) {
- return DriverManager.getConnection(job.get(DBConfiguration.URL_PROPERTY));
- } else {
- return DriverManager.getConnection(
- job.get(DBConfiguration.URL_PROPERTY),
- job.get(DBConfiguration.USERNAME_PROPERTY),
- job.get(DBConfiguration.PASSWORD_PROPERTY));
- }
- }
- String getInputTableName() {
- return job.get(DBConfiguration.INPUT_TABLE_NAME_PROPERTY);
- }
- void setInputTableName(String tableName) {
- job.set(DBConfiguration.INPUT_TABLE_NAME_PROPERTY, tableName);
- }
- String[] getInputFieldNames() {
- return job.getStrings(DBConfiguration.INPUT_FIELD_NAMES_PROPERTY);
- }
- void setInputFieldNames(String... fieldNames) {
- job.setStrings(DBConfiguration.INPUT_FIELD_NAMES_PROPERTY, fieldNames);
- }
- String getInputConditions() {
- return job.get(DBConfiguration.INPUT_CONDITIONS_PROPERTY);
- }
- void setInputConditions(String conditions) {
- if (conditions != null && conditions.length() > 0)
- job.set(DBConfiguration.INPUT_CONDITIONS_PROPERTY, conditions);
- }
- String getInputOrderBy() {
- return job.get(DBConfiguration.INPUT_ORDER_BY_PROPERTY);
- }
-
- void setInputOrderBy(String orderby) {
- if(orderby != null && orderby.length() >0) {
- job.set(DBConfiguration.INPUT_ORDER_BY_PROPERTY, orderby);
- }
- }
-
- String getInputQuery() {
- return job.get(DBConfiguration.INPUT_QUERY);
- }
-
- void setInputQuery(String query) {
- if(query != null && query.length() >0) {
- job.set(DBConfiguration.INPUT_QUERY, query);
- }
- }
-
- String getInputCountQuery() {
- return job.get(DBConfiguration.INPUT_COUNT_QUERY);
- }
-
- void setInputCountQuery(String query) {
- if(query != null && query.length() >0) {
- job.set(DBConfiguration.INPUT_COUNT_QUERY, query);
- }
- }
-
-
- Class<?> getInputClass() {
- return job.getClass(DBConfiguration.INPUT_CLASS_PROPERTY, NullDBWritable.class);
- }
- void setInputClass(Class<? extends DBWritable> inputClass) {
- job.setClass(DBConfiguration.INPUT_CLASS_PROPERTY, inputClass, DBWritable.class);
- }
- String getOutputTableName() {
- return job.get(DBConfiguration.OUTPUT_TABLE_NAME_PROPERTY);
- }
- void setOutputTableName(String tableName) {
- job.set(DBConfiguration.OUTPUT_TABLE_NAME_PROPERTY, tableName);
- }
- String[] getOutputFieldNames() {
- return job.getStrings(DBConfiguration.OUTPUT_FIELD_NAMES_PROPERTY);
- }
- void setOutputFieldNames(String... fieldNames) {
- job.setStrings(DBConfiguration.OUTPUT_FIELD_NAMES_PROPERTY, fieldNames);
- }
- }